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81.
Lysozyme concentration in the gastric juice of 34 patients with peptic ulcer and 10 practically healthy persons was studied. In the patients with peptic ulcer the lysozyme levels in the gastric juice were found to be lower. A significant decrease in the lysozyme concentration was observed in the patients suffering from peptic ulcer for more than 2 years. During the first months of the disease increased levels of lysozyme were recorded. Relationship between the lysozyme concentration in the gastric juice and the acidity of the gastric contents was shown. Decreased concentrations of lysozyme were more pronounced in the patients with increased levels of hydrochloric acid.  相似文献   
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AIM: The expression of CD95(Fas/APO-1) antigen was studied on bone marrow cells of 19 MDS patients, peripheral blood blast cells of 15 acute myeloid leukemia (AML) patients, blast cells and granulocytes of 68 patients with chronic myeloid leukemia (CML)--24 in chronic, 9 in accelerated phase and 35 in blastic crisis (BC)--by indirect surface immunofluorescence assay using flow cytometry (FACScan, Becton Dickinson, USA). RESULTS: CD95(Fas/APO-1) antigen was revealed on bone marrow cells of 8 out of 19 (36.8%) MDS patients; the percentage of antigen-positive cells was 38.1 +/- 19.2%; on 45.5 +/- 22.8% of cells in 6(45%) of 15 AML patients. Fas/APO-1 antigen was totally absent in CML chronic stage; its expression was found in 34% (12 of 35) of our patients with CML BC on peripheral blood blasts and in 56% (5 of 9) on peripheral blast cells of CML patients in acceleration phase. CONCLUSION: The data on overall survival of CD95-positive MDS patients suggest that the presence of Fas antigen is a favorable prognostic sign for patients with MDS. The patients from CD95-negative group represent a risk group both for survival and AML transformation. In CML BC group the survival does not depend upon Fas-antigen expression.  相似文献   
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Elevated aminotransferases activities are frequent in medical practice. In acute elevations, the mains causes are generally easily found (viral, drug-induced, toxic, ischemic). In moderate or prolonged elevations, the most frequent causes are steatosis (alcoholic, diabetes, obesity) and chronic hepatitis (viral B, D, C, drug-induced and auto-immune diseases.  相似文献   
86.
The aim of this work was to develop new bifunctional alkylating agents which damage DNA in a selective manner. In order to extend our previously published work on conformationally restricted nitrogen mustards containing one piperidine ring, new bispiperidine derivatives were designed with varying lengths of carbon chain between the two rings and structure-activity relationships in these systems were studied. Thus samples of new bispiperidine salts 22-26 with chloromethyl groups at the 2-positions and a bridge between the two nitrogen atoms of 2-6 carbon atoms were synthesized. The analogous new bis(p-nitrophenylcarbamates) 17-21 were also prepared. The free bases were designed to be bifunctional alkylating agents via aziridinium ion formation with different distances between the two alkylating sites. The bispiperidines 22-24 were shown to alkylate guanines at the 7-position in the major groove of DNA more selectively than melphalan. The bispiperidine 22 with the shortest two carbon bridge was the most reactive but it was less cytotoxic than melphalan in a human colon carcinoma cell line (IC50 value approximately 30 microM) and in a human chronic myeloid leukaemia cell line (IC50 value approximately 12 microM). The most cytotoxic compound in the latter cell line was the carbamate 17, with an IC50 value of approximately 0.3 microM, and carbamates 17, 19 and 20 were most potent in a panel of human ovarian carcinoma cell lines. These compounds also showed circumvention of acquired cisplatin resistance in three paired cell lines. The carbamates 17-21, however, were less efficient at alkylating and cross-linking naked DNA than the bispiperidines 22-26.  相似文献   
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88.
The effects of high-energy ionizing radiation on the behavior and output frequency of electronic oscillators, whose frequency-determining elements were quartz crystals operating in the vicinity of 5 Mc, have been studied. Both fundamental- and fifth-overtone crystals were studied over a dose range from 3,000 rads (Si) to 2 Mrads (Si). The crystals studied were of two types: (1) standard commercial precision crystals fabricated from natural quartz with Q's of approximately 2.5 × 106 for the fifth overtone and 4 × 105 for the fundamental, and (2) special fifth-overtone crystals fabricated from swept pure Z-growth synthetic quartz. The natural quartz showed much larger changes in frequency and transient loss of Q than the swept synthetic crystals. The crystals were incorporated into commercial precision oscillator circuits and maintained in a temperature-controlled oven. The radiation doses (both 25-MeV electrons and 10-MeV peak bremsstrahlung gamma rays) were provided by the General Atomic electron linear accelerator. The radiation was collimated to irradiate only the crystal. The oscillator output signal was monitored with an oscilloscope during and after the radiation burst, and the frequency was measured by cycle counting for 10-or 100-sec time intervals. The precision of the frequency measurements was ±2 parts in 108 for the 10-sec intervals and ±2 parts in 109 for the 100-sec intervals. Electrons and gamma rays were shown to have the same effect on the crystals; therefore, most of the work was done with electrons because of the convenience of accumulating large doses in 4.5-psec pulses.  相似文献   
89.
The deaths of 10 heroin body packers are reported and contrasted to those of cocaine body packers. Only one was a woman, and all were traveling to or from Colombia. Drug packets deteriorated in the gastrointestinal tract and caused the deaths of eight victims. Accomplices removed drug packets from two of these smugglers after death occurred. One died of peritonitis stemming from a small-bowel obstruction caused by the drug packets, and one died from the recreational use of heroin (nasally ingested). The heroin recovered was < or = 881 g, and the drug purity of the contraband in three cases was between 65% and 73%. Blood concentrations of morphine were < 1.0 mg/L in four victims; no morphine was detected in the smuggler who died of peritonitis. However, two victims had blood morphine concentrations of 4.4 mg/L and 6.7 mg/L, respectively, and three had morphine concentrations of 35.8, 39.4, and 52.6 mg/L, respectively. Fatal heroin body packing differs from cocaine body packing in that individuals may have extremely high drug levels in their blood and their accomplices appear to be more likely to abandon them in a remote location after attempting to remove the drug packets after death has occurred.  相似文献   
90.
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